1. Field of the Invention
The invention relates to regenerative heat exchangers in which a fixed mass of heat absorbent material is alternately subjected to the flow of hot gas and cooler air in order that heat content of the gas may be transferred to the cool air through the intermediary of the heat absorbent material. Valves which direct the flow of air and gas to and from a fixed mass of heat exchange element are sequentially opened and closed to obtain the desired cycle of operation. An inherent defect in this type of apparatus lies in the fact that a quantity of heated fluid always remains in the heat exchanger after valves which control such flow therethrough are closed. Upon directing a succeeding fluid through the heat exchanger, the fluid entrained in the heat exchanger is then pushed out of the heat exchanger by said fluid and exhausted to the atmosphere to be forever lost.
Inasmuch as air when heated, then lost represents a loss of effectiveness, it is also an economic loss since it requires larger fans which in turn require more power. This patent attempts to alleviate this situation by providing an arrangment that forces entrained air to flow to its original destination for full utilization.
2. Description of the Prior Art
U.S. Pat. Nos. 1,845,239 and 3,741,286 are directed to valve type regenerator arrangements that disclose known arrangements for purging entrained gas from passageways within the regenerator. Although such arrangements might be modified to similarly purge entrained air from the heat exchanger, they would not provide the simple but effective arrangement herein disclosed.